The present invention is directed to an electronic lamp, and to the connection between a lamp and lamp electronics which control operation of the lamp.
Lamp systems including a lamp and electronics, supplied by a power source are known in the art. A problem with known lamp systems is that existing connection schemes between the power source, lamp and electronics, do not allow for the electronics to be an integral part of the lamp. Rather, the electronics are commonly set apart from the lamp within the system housing or fixture.
Attempts have been made to closely attach the lamp and the electronics. An example of such a system is described in two patents to Smallwood et al., U.S. Patent Nos. 5,485,057 and 5,654,609. The Smallwood et al. patents set forth two embodiments of a gas discharge lamp system. The first embodiment is directed to high frequency systems. In this situation a.c. power conditioning may be designed as a master controller. Then a separate miniaturized high-frequency oscillator and transformer is formed as a module and attached to the end of the lamp. In low-frequency embodiments, Smallwood et al. describes placing a power oscillator circuit within a gas discharge lamp envelope, eliminating components which are presently mounted external to the lamp. However, in Smallwood et al. conductor wires extend the length of the lamp envelope to a second heater element to connect the second heater element to the oscillator module. These conductor wires are noted as being preferably positioned along the inner surface of the envelope to minimize damage in handling.
German Patent DE 195 12 307 A1 to Reinig, discloses some sort of electronics being located on a single end of a lighting tube. However, in Reinig it is also necessary to provide a conductor wire along the length of the lamp to complete the electrical connection.
Thus, in both the Smallwood et al. patents and the Reinig patent, a wiring connection is provided directly from the electronics controlling operation of the lamp to the opposite end of the lamp.
A problem with having exterior wires running the length of the lamp is the likelihood of such connections becoming dislodged or otherwise broken. This design will also interfere or block portions of light output from the lamp. An alternative suggested in Smallwood et el. is to run the conductor along the inner surface of the envelope. However, Smallwood et al. does not describe how this is to be accomplished. Running a conductor within the envelope increases the manufacturing complexity and adds costs to the system. Further, a lamp having a conductor within the lamp envelope is subject to a hostile environment which may act to accelerate the deterioration of the lamp.
It is therefore considered beneficial to design a lamp system where the lamp electronics are positioned on an end of the lamp in an integral relationship with the lamp, whereby the integral lamp/lamp electronics unit may be removed as a single component from the housing of the system. It would also be desirable for the integral lamp/lamp electronics unit to be supplied by the power source without requiring a conductor wire to be positioned along the length of the lamp, on the interior of the glass envelope of the lamp or attached to the exterior of the glass envelope of the lamp.
An integrated lamp/lamp electronics unit includes a lamp having a first end with first end electrical terminals, and a second end with second end electrical terminals. An end cap having an interior section is placed into electrical connection with the first end electrical terminals at the first end of the lamp. Lamp electronics are configured to control operation of the lamp and are connected only to the second end electrical terminals. The lamp electronics have a configuration substantially matching the second end of the lamp portion. The electronic circuit is placed within the interior of a lamp electronics end cap, and the end cap is attached in a permanent relationship to the second end of the lamp.